Experimental study on prediction of rock burst with pipe thrust method

In order to predict mine rock burst,the method of thrust of drill pipe is used to estimate the risk of rock burst in coal mine. Through the establishment of dynamic model of coal seam drilling process,the relationship between the thrust of drill pipe and the stress of coal is obtained. Using the independently developed test system of thrust test with drill pipe,the change law of thrust value under different coal seam stresses is tested in the laboratory. Experimen- tal results show that with the increase of drilling depth,the thrust value increases first and then stabilizes and final de- creases gradually. Under the same drilling and drilling tool conditions,an in-situ experiment of drilling in underground mine is conducted,the analysis of experimental data discovers that there is a good corresponding relationship among drill cuttings,drill pipe thrust and coal stress. It proves the feasibility of predicting the impact risk using drill rod thrust. The research results provide a method for the prediction of the mine rock burst dynamic disaster and the deter- mination of dangerous area. It can be used as a reference index of forecast shock hazard.